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| Question 1068287:  AB is a chord of a segment of a circle and C is any point on the arc of the segment .Prove that m
 Found 3 solutions by  ikleyn, Fombitz, KMST:
 Answer by ikleyn(52879)
      (Show Source): 
You can put this solution on YOUR website! . 
 
m < CAB  +m < CBA  = 180 - m < c.
m < C is the same for all positions of the point C in the circle and is half of the measure of the arc AB, 
      since the angle C is an inscribed angle.
It implies that  m < CAB  +m < CBA  = const,
QED.
 
 On inscribed angles see the lesson
 - An inscribed angle in a circle,
 in this site.
 
 
 Also, you have this free of charge online textbook on Geometry
 - GEOMETRY - YOUR ONLINE TEXTBOOK
 in this site.
 
 The referred lesson is the part of this textbook under the topic
 "Properties of circles, inscribed angles, chords, secants and tangents".
 
 
 
Answer by Fombitz(32388)
      (Show Source): Answer by KMST(5328)
      (Show Source): 
You can put this solution on YOUR website! Angles CAB and CBA are inscribed angles that intercept arcs CA and CB.
 Each of those angles measures half of
 the measure of the intercept arc.
 The sum of the measures of those angles
 is half the sum of the measures
 of the intercepted arcs CA and CB.
 The sum of the measures of those arcs
 Is the measure of arc AB,
 regardless of the position of point C.
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